ENGINE TOP END 4-29
Cylinder, Piston
Piston Ring, Piston Ring Groove Wear
•
Check for uneven groove wear by inspecting the ring seat-
ing.
The rings should fit perfectly parallel to the groove sur-
faces. If not, the piston must be replaced.
•
With the piston rings in their grooves, make several mea-
surements with a thickness gauge [A] to determine piston
ring/groove clearance.
Piston Ring/Groove Clearance
Standard:
Top
0.03
∼
0.07 mm (0.0012
∼
0.0028 in.)
Second
0.02
∼
0.06 mm (0.0008
∼
0.0024 in.)
Service Limit:
Top
0.17 mm (0.0067 in.)
Second
0.16 mm (0.0063 in.)
Piston Ring End Gap
•
Place the piston ring [A] inside the cylinder, using the pis-
ton to locate the ring squarely in place. Set it close to the
bottom of the cylinder, where cylinder wear is low.
•
Measure the gap [B] between the ends of the ring with a
thickness gauge.
Piston Ring End Gap
Standard:
Top
0.20
∼
0.35 mm (0.0079
∼
0.0138 in.)
Second
0.20
∼
0.35 mm (0.0079
∼
0.0138 in.)
Oil
0.2
∼
0.7 mm (0.008
∼
0.028 in.)
Service Limit:
Top
0.7 mm (0.0276 in.)
Second
0.7 mm (0.0276 in.)
Oil
1.0 mm (0.0394 in.)
Cylinder Inside Diameter
•
Since there is a difference in cylinder wear in different di-
rections, take a side-to-side and a front-to-back measure-
ment at each of the 3 locations (total of 6 measurements)
shown in the figure.
If any of the cylinder inside diameter measurements ex-
ceeds the service limit, the cylinder will have to be bored
to oversize and then honed.
[A] 10 mm
[B] 60 mm
[C] 20 mm
Piston Diameter
Standard:
74.000
∼
74.012 mm (2.9134
∼
2.9139 in.)
Service Limit: 74.11 mm (2.9177 in.)
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Инструкции и руководства похожие на KAWASAKI ER5 (2004)
